Exhibit 99.1

Name and Address of Reporting Person:	Valinor Management, L.P.
	510 Madison Avenue, 25th Floor
	New York, NY 10022
Issuer Name and Ticker or Trading Symbol:	NextDecade Corporation [NEXT]
Date of Earliest Transaction to be Reported
(Month/Day/Year):	August 30, 2018

Footnotes to Form 4

(1) Represents 4,175,522 shares directly held by Valinor Capital Partners, L.P. (“Valinor Capital”) (including 342,892 shares issuable pursuant to that certain Agreement and Plan of Merger, dated April 17, 2017, by and among Harmony Merger Corporation, Harmony Merger Sub, LLC, NextDecade, LLC and certain members of NextDecade, LLC and entities affiliated with such members (the “Merger Agreement”) upon the satisfaction of certain milestones).  Valinor Management, L.P. (“Valinor Management”) serves as investment manager to Valinor Capital. David Gallo is the Founder, Managing Partner, and Portfolio Manager of Valinor Management and is the managing member of Valinor Associates, LLC (“Associates”), which serves as general partner to Valinor Capital.  Each of Valinor Management, Associates and David Gallo may be deemed to beneficially own the securities held by Valinor Capital and each of Valinor Management, Associates and David Gallo disclaims beneficial ownership of the reported securities, except to the extent of its or his pecuniary interest.

(2) Represents 11,880,341 shares directly held by Valinor Capital Partners Offshore Master Fund L.P. (“Capital Partners Offshore Master”) (including 975,608 shares issuable pursuant to the Merger Agreement upon the satisfaction of certain milestones).  Valinor Management serves as investment manager to Capital Partners Offshore Master.  David Gallo is the Founder, Managing Partner, and Portfolio Manager of Valinor Management and is the managing member of Associates, which serves as general partner to Capital Partners Offshore Master.  Each of Valinor Management, Associates, and David Gallo may be deemed to beneficially own the securities held by Capital Partners Offshore Master and each of Valinor Management, Associates and David Gallo disclaims beneficial ownership of the reported securities, except to the extent of its or his pecuniary interest.

(3) Represents 5,245,555 shares held directly held by VND Partners, L.P. (“VND Partners”) (including 431,584 contingent shares issuable pursuant to the Merger Agreement upon the satisfaction of certain milestones).  Valinor Management serves as investment manager to VND Partners. David Gallo is the Founder, Managing Partner, and Portfolio Manager of Valinor Management and is the managing member of Associates, which serves as general partner to VND Partners.  Each of Valinor Management, Associates, and David Gallo may be deemed to beneficially own the securities held by VND Partners and each of Valinor Management, Associates, and David Gallo disclaims beneficial ownership of the reported securities, except to the extent of its or his pecuniary interest.

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Joint Filer Information

Name of Joint Filer:	Valinor Capital Partners Offshore Master Fund, L.P.
Address of Joint Filer:	c/o Valinor Management, L.P.
	510 Madison Avenue, 25th Floor
	New York, NY 10022
Relationship of Joint Filer to Issuer:	10% Owner; Director
Issuer Name and Ticker or Trading Symbol:	NextDecade Corporation [NEXT]
Date of Earliest Transaction to be Reported
(Month/Day/Year):	August 30, 2018
Designated Filer:	Valinor Management, L.P.
Signature:
Valinor Capital Partners Offshore Master Fund, L.P.

/s/ David Angstreich

Name:	David Angstreich
Title:	Chief Operating Officer

August 31, 2018

Date

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